Ultracold gases for quantum simulation of non-equilibrium systems

用于非平衡系统量子模拟的超冷气体

• 批准号: RGPIN-2014-06618
• 负责人: LeBlanc, Lindsay
• 金额: $ 1.6万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=656924
• 关键词: Ultracold; gases; quantum; simulation; non

In behaviour like superconductivity, where electricity flows with exactly zero loss, relationships between particles at different positions in the system, called "quantum correlations," provide system-wide communication that leads to many-body behaviour. Many-body cooperativity translates quantum effects (usually associated with microscopic particles) to a human scale, where they are accessible and exploitable. The probabilistic nature of quantum mechanics makes predicting these phenomena with calculations on conventional computers feasible only for simple models or small numbers of particles. "Quantum simulation" was proposed by Feynman as an alternative approach. Instead of relying on classical computers to model these behaviours, he reasoned, let quantum mechanics do the work. With real quantum particles whose interactions and environments are tailored to emulate many-body models, calculations are performed by allowing Nature to act according to the laws of quantum mechanics. Solutions are obtained via experimental measurement.**In this research program, we will use laser-cooled ultracold quantum gases as the medium for quantum simulation. At temperatures just billionths of a degree above absolute zero, random motion associated with temperature is all but eliminated, yielding both system-wide quantum correlations and unparalleled control over interactions and environments. These experiments will reveal the essential ingredients leading to a model's quantum many-body order, by examining questions about its energy, ground state, and dynamics. **The Ultracold Quantum Gases Laboratory will focus on many-body systems whose correlations arise as a result of "artificial gauge fields." In these environments, an internal property of the quantum particle, such as "spin," is intrinsically related to an external property, such as momentum. A familiar example of a gauge field is a magnetic field, where these relationships are spatially dependent. Along with engineering artificial magnetic fields, we will implement alternative spin-momentum correlations, some of which are thought to exhibit "topological order:" unique non-local order that is especially good at preserving quantum correlations in the presence of environmental disturbances. Focussing our attention on non-equilibrium properties will provide insight into the factors that control the growth, preservation, and demise of quantum correlations.**This research program makes important contributions to Canada's leadership in quantum technology. By identifying specific conditions under which quantum materials will exhibit robust long-range correlations, this research will provide valuable input to engineers designing new quantum materials and devices. By providing the theoretical physics research community with measurement-based results of quantum many-body models, this research will encourage the pursuit of novel many-body phenomena. In bridging the divide between theoretical conception and practical realization, the research will facilitate the development of next-generation quantum materials, such as those that provide efficient energy transmission with better superconducting materials, or those that offer an exponential increase in computational capacity with devices that process and store resilient quantum correlations. This laboratory will provide young scientists with the opportunity to gain new skills by developing and using precision laser systems, custom electronic controls, and ultrahigh vacuum systems. As they continue their careers, these highly qualified personnel will be able to offer the precision of atomic physics techniques to a variety of industries and research disciplines.

在像超导这样的行为中，电流的流动完全为零损耗，系统中不同位置的粒子之间的关系，称为“量子相关性”，提供了导致多体行为的系统范围内的通信。 多体协同性将量子效应（通常与微观粒子有关）转化为人类尺度，在那里它们是可访问和可利用的。量子力学的概率性质使得在传统计算机上预测这些现象仅适用于简单模型或少量粒子。“量子模拟”是费曼提出的一种替代方法。 他认为，与其依赖经典计算机来模拟这些行为，不如让量子力学来完成这项工作。对于真实的量子粒子，它们的相互作用和环境都是为了模拟多体模型而定制的，计算是通过允许大自然根据量子力学定律进行的。通过实验测量获得解决方案。**在本研究计划中，我们将使用激光冷却的超冷量子气体作为量子模拟的介质。在比绝对零度高十亿分之一度的温度下，与温度相关的随机运动几乎被消除，产生了系统范围的量子关联和对相互作用和环境的无与伦比的控制。这些实验将揭示导致一个模型的量子多体秩序的基本成分，通过检查其能量，基态和动力学的问题。** 超冷量子气体实验室将专注于多体系统，其相关性是“人工规范场”的结果。在这些环境中，量子粒子的内部性质，如“自旋”，与外部性质，如动量，有内在的联系。规范场的一个熟悉的例子是磁场，其中这些关系是空间依赖的。沿着工程人工磁场，我们将实现替代的自旋-动量关联，其中一些被认为表现出“拓扑序“：独特的非局域序，特别擅长在环境扰动存在下保持量子关联。把我们的注意力集中在非平衡性质上，将有助于我们深入了解控制量子关联的增长、保持和消亡的因素。该研究计划为加拿大在量子技术领域的领导地位做出了重要贡献。通过确定量子材料将表现出强大的长程相关性的特定条件，这项研究将为工程师设计新的量子材料和设备提供有价值的投入。通过为理论物理研究界提供量子多体模型的测量结果，这项研究将鼓励对新颖的多体现象的追求。在弥合理论概念和实际实现之间的鸿沟时，该研究将促进下一代量子材料的开发，例如那些通过更好的超导材料提供有效能量传输的材料，或者那些通过处理和存储弹性量子相关性的设备提供计算能力指数增长的材料。该实验室将为年轻的科学家提供机会，通过开发和使用精密激光系统，定制电子控制和真空系统来获得新技能。随着他们继续他们的职业生涯，这些高素质的人员将能够提供原子物理技术的精度，以各种行业和研究学科。